Calculation of Torque for Drive Pulley of Roller Conveyor

[hardja]

Anyone can help me to calculate the Torque for Drive Pulley of Rolling Conveyor?
The details below:
- Roller Conveyor : length = 18m (speed of the belt conveyor is 2.5m / sec)
- Conveyor consists of 25 roller, 1 drive pulley & 1 tail pulley
- Total load of the conveyor : 5,500 kg

To move the conveyor, we install Drive Pulley with diameter of 550mm, and connected to Gear Box (RPM = 95) + Motor (5,5 HP ; RPM 1,500)

How do we calculate how much is the Torque of the Drive Pulley?

 

[sophiecentaur]

Power is linear speed times force. (F v)
Also, it's also rotational speed times torque (2πf τ)
where f is revs per second

You just put these on the sides of an equation and put in what you know to what you want to find out.

 

[russ_watters]

It is difficult to find the torque required because you need to know friction, which is difficult to estimate. A company I know who makes conveyors for large animal cages assumes a friction coefficient of 1.0, in other words if you hang the load off the side the conveyor and tilt the machine up, it would be strong enough to lift it vertically.

 

[hardja]

Power is linear speed times force. (F v)
Also, it's also rotational speed times torque (2πf τ)
where f is revs per second

You just put these on the sides of an equation and put in what you know to what you want to find out.

Can you help which equation I should use?
I'm new with conveyor matters but got a job that asked me to install Belt Conveyor.

Appreciate your help.

 

[sophiecentaur]

Can you help which equation I should use?
I'm new with conveyor matters but got a job that asked me to install Belt Conveyor.

Appreciate your help.

Sorry - that was a Maths thing. What I meant was that you put those two expressions equal to each other - which makes an equation. So
Linear speed times force = rotational speed times torque
You know everything but the torque so you take rotational speed onto the other side to get the torque:
Torque = linear speed times force / rotational speed
(not forgetting the 2pi in my other post and to convert rpm into revs per second)
That should do it.

 

[CWatters]

When you posted this Question on another thread I answered as follows...

Do you happen to know if a 5.5hp motor is powerful enough for this job? If you do then you can estimate the max torque assuming the motor is delivering 5.5HP at 1500rpm...

5.5 HP = 4125W

1500rpm = 157 Radians/second

So the torque at the motor is 4125/157 = 26Nm

The gearbox reduces rpm and multiplies the torque so torque at the output of the gearbox/drive pulley should be something like..

26 * 1500/95 = 410Nm

But that could be greatly exceeded. I can think of a lot of ways the torque could be higher for periods of time. Some examples..

Depending on the type of motor and how it's controlled the starting torque might be much higher.

You say the load is 5500kg. The transit time is 18/2.5 = 7.2 seconds. So every second 760kg is being dumped on one end of the conveyor belt and has to be accelerated to 2.5m/s. If the load is lumpy the torque might spike higher?

What happens if the belt with 5500Kg on it has to be stopped in a hurry or there is a power cut?

I'm not an expert on these systems. Google found a guide to the basics. Looks complicated to me.

http://www.krk.com.br/html/produtos/phoenix/Design_Fundamentals.pdf

As others have said.. I don't think you have enough information to calculate it any other way. You need info on the friction in the rollers etc when carrying 5500KG. Ask the manufacturer perhaps?